Have you had any luck with this id? I have recently come across the same marks on a serving plater with this heraldry on the front.
Hello! I have found a plate with these marks as well, I cannot find any information on it. Has anyone got it figured out yet? Approximate year? Anything? Also my plate has a seam down the middle on one side (not the back) Wonder if it had a divider that fell off. Any information will be appreciated!